MICROBIOLOGY CLINICAL (grech, mikros small + biology) — the applied section of medical microbiology.
In the 70th years the great value was gained mikrobiol. researches of the secondary infectious processes caused by opportunistic microorganisms. In this regard there was a term «clinical microbiology» having a little conditional character. M to. is engaged in diagnosis of infectious diseases, and also the pyoinflammatory processes complicating a current of somatopathies and the postoperative period, to-rye develop at patients preferential against the background of a conflict situation between immunobiological protective forces of an organism and opportunistic microorganisms.
Use of modern methods of treatment — antibacterial drugs, hormones, immunodepressants, radiotheraphy, etc. — led to change in ecology of microorganisms and reactivity of a macroorganism concerning opportunistic microbes that caused growth of the infectious complications arising in hospitals (intrahospital infections). Causative agents of intrahospital infections most often are golden staphylococcus, gram-negative opportunistic pathogenic bacteriums, such as escherichias, proteas, a pyocyanic stick (see. Intrahospital infections ).
Mikrobiol, researches at secondary infectious processes have a number of the features caused by the fact that causative agents of these diseases belong to opportunistic microflora.
Considerably the circle of the microorganisms which are subject to allocation from the patient and to the subsequent studying extends. From patol, material allocate and study not any certain type of the activator as it takes place during the work with pathogenic microorganisms, and all types which are there as microorganisms can be activators of infectious process, pathogenic properties to-rykh are unknown.
Often from the studied material associations of microorganisms are allocated. The microorganisms entering into association allocate in pure growths (see. Bacterial culture ) also study quantitative structure, biol, properties, and also sensitivity to antibacterial: to drugs at each culture.
Belonging of activators of infectious complications to opportunistic group of microorganisms causes the necessity to establish them etiol, a role in infectious process. For this purpose use a number of methods. The quantitative method consisting in definition of «critical number» of microbes in a certain volume of the studied material concerns to them. Definition of degree of an obsemenennost of clinical material allows to differentiate infectious process from contamination by normal microflora. So, e.g., at bacterial, a research of urine define degree bacteriurias (see) — number of microbic cells in 1 ml of urine. The bacteriuria equal above 10^5, demonstrates existence of an infection in uric ways, lower degree of a bacteriuria occurs at healthy people and is result of contamination of urine normal microflora of uric ways.
Study also dynamics of change of quantity of microbes during a disease: increase of microbes of a certain look demonstrates their participation in infectious process. A certain value for judgment about etiol, roles of microorganisms has frequency of their allocation during a disease.
Comprehensive study of properties of the marked-out cultures is represented important: their definition serol, and biol, options, sensitivity to phages and other signs helping to identify a look (see. Identification of microbes ) and to mark strains. Marking of strains is used during the carrying out epidemiol, researches at intrahospital infections: she helps to establish a source of an infection, to reveal ways of distribution of the activator in the hospital environment. Special value has it for identification of the hospital strains of the microorganisms circulating in the hospital environment and causing the heaviest outbreaks of intrahospital infections.
One of features of the infectious process caused by opportunistic microorganisms is rather weak immune response of an organism: antibodies in serum of the patient collect in a low caption, increase in an antiserum capacity happens slowly. Therefore it is necessary to define change of an antiserum capacity in the pair serums received from patients at the beginning and the end of a disease; are at the same time applied to detection of antibodies a little immunol, tests, various on the sensitivity; reactions carry out with a set of antigens.
Interpretation of results mikrobiol. researches at the infections caused by opportunistic microorganisms, especially in case of their belonging to normal microflora of a human body causes quite often essential difficulties. To prove etiol, a role of the culture which is marked out from an organism it is possible only at a complex research: identification of species of microbes, their of «critical number» in the studied material, repeated allocation from the patient, and also identification immunol, shifts in blood serum of the patient. For final assessment of the obtained data comparison of results mikrobiol matters. researches about a wedge, a picture of a disease and results of other analyses.
The important section M. to. studying of sensitivity of infestants to germicides is. Among opportunistic microorganisms many types have high natural medicinal substances resistance, e.g. Xing a purulent stick, proteas, bacteroids, or easily gain medicinal stability, napr, staphylococcus, klebsiyella, escherichias, etc. (see. Medicinal stability of microorganisms ). Therefore for a right choice of a germicide and appointment it in effective doses needs to be defined sensitivity to it at the cultures which are marked out from patients.
For increase in efficiency of antibacterial therapy studying of pharmacokinetics of antibacterial substances, their side effect on an organism of patients is necessary (allergic reactions, immunodepressive and toxic effect, etc.). These researches are also a subject of studying of M. to. On the basis of the obtained data the optimum mode of use of chemotherapeutic substances is developed, individual schemes of administration of medicinal substances are established.
See also Microbiology .
Bibliography: V. D.'s white hares, etc. Hospital infection, M., 1976; Intrahospital infections: the guide to laboratory methods of researches, under the editorship of M. T. Parker, Copenhagen, WHO, 1979; Loshontsid. Intrahospital infections, the lane with Wenger., M., 1978; Petrovsky V. G. and M and r to about O. P. Mikroflor of the person is normal also of pathology, M., 1976; Control of hospital infections, ed. by E. J. L. Lowbury, L., 1975.
S. D. Voropayeva.